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EVOLUTION AND CLASSIFICATION. . 


ADDRESS 


BY 


CHARLES E. BESSEY, 


VICE-PRESIDENT, SECTION G, 


BEFORE THE 


AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE, 


AT THE MADISON MEBRETING, 


AUGUST, 1893. 


PRINTED BY 


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1894, 


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ADDRESS 


BY 


CHARLES EK. BESSKY, ‘ 


VICE PRESIDENT, SECTION G. 
EVOLUTION AND CLASSIFICATION. 


MEMBERS AND FELLOWS OF THE SECTION OF BOTANY: 


Ir is fitting in this address, which opens the work of the new 
section of botany, when for the first time in the history of the As- 
sociation we meet officially as a body of botanists, that I should 
give voice to'thoughts which have come to many of us during these 
later years. As. we have gathered up the scattered masses of 
botanical knowledge, laboriously wrought out by many isolated 
workers, and attempted to fit them together into a consistent 
whole, which should outline the structure of the temple Botany, we 
have found that the workmen have not always followed the same 
architectural plan, and have often used different units of measure- 
ment. With the increasing specialization so noticeable year by 
year there is a corresponding lack of coordination of work. To 
this lack of codrdination, this want of unity of measurement, this 
misunderstanding of plan, we can no longer close our eyes, and I 
therefore feel free to invite your attention to the following some- 
what summary discussion of the causes of the present unsatisfac- 
tory condition, in the hope that we may thereby be enabled to see 
how we may make some improvement. 

All botanical knowledge finally culminates in some kind of clas- 
sification. The work of the morphologist and the physiologist no 
less than that of the professed systematist all find their final ex- 
pression in Classification, The idea which has sometimes found 


(237) 


238 | SECTION G. 


favor among botanical workers, that there are some departments of 
botany which have nothing whatever to do with classification, is 
entirely erroneous. It may be true that a particular worker may 
make no such use of his results, but it is true nevertheless, that his 
results will be used and given place and meaning in the great struc- 
ture which we know as the System of Plants. We must not over- 
estimate the value of the work done in particular fields. No one 
to-day will deny the importance of the work of the histologist who 
constantly surprises and astonishes us with the depth of insight 
which he attains of the minute structure of the cell. We follow the 
morphologist as he skillfully traces the homologies of organs in re- 
lated groups of plants, and we watch with delight the cunningly 
devised experiments of the physiologist whereby he is enabled to 
penetrate further and further the mystery of plant life. ‘The facts of 
histology, morphology and physiology are of great biological im- 
portance, but the greatest of all biological facts is that the world 
is peopled with living things. We may group and arrange in 
orderly sequence the histological facts of the science: we may do 
likewise with the facts which the morphologist has discovered: we 
may make a classification of all the known physiological facts, but 
beyond and above these lies the greatest grouping of all, the group- 
ing in orderly sequence of the organisms themselves whose histol- 
ogy, morphology and physiology we have studied. Do not mis- 
understaud me. When I claim the first place in importance forthe 
classifiacation of living things, do not for a moment suppose that 
this implies first in point of time in the study. Because the super- 
structure is the culmination of the building, we do not necessarily 
begin with it and leave the foundation until later. 

3ut all this is preliminary, and I have referred to it merely to 
be sure that we are fully agreed as to certain fundamentals. 

It is now a full third of a century since a great light was first 
turned upon all biological problems by the formulation of the doc- 
trine of evolution by the master mind of Darwin. In its light many 
puzzles have been solved, and many facts hitherto inexplicable have 
been made plain. Wenow know what relationship means, and we 
have given a fuller meaning to the natural system of classification. 
From the new point of view a natural classification is not merely 
an orderly arrangement of similar organisms. It is an expression 
of genetic relationship. The present similarity of two organisms 
is not enough to determine their relationship, or place in a system, 


ADDRESS BY CHARLES E. BESSEY. 239 


Common origin must be inferred in order that relationship shall be 
assumed. 

Furthermore, in the light of evolution we now see the meaning of 
many reduced structures whose significance was formerly not at 
all or but vaguely understood, The rudimentary stamens of the 
Labiate, and Scrophulariacese, the rudimentary ovules of some 
Composite and Graminez, the rudimentary calyx of most Um- 
belliferse and many Composite are no longer difficult to under- 
stand. We have become familiar with the fact that degradation is 
a prominent factor in the vegetable kingdom. Evolution has by 
no means always involved an advance in structural complexity. 
Even in those cases where the organism itself has advanced, fre- 
quently some of its organs have undergone degeneration. Still 
more frequently the whole organism has suffered structural degra- 
dation, and we commonly assign it a lower place. Often this 
catagenesis is a result of parasitism or saprophytism, as is so well 
illustrated in the ‘* fungi,” where the degradation has gone so far 
that their relationship has to a great degree been obscured. Among 
flowering plants we have numerous instances of degradation 
through parasitism, as, for example, the species of Cuscuta, the 
Orobanchacew, Loranthacez, Rafflesiaceze, Balanophoraces, ete. 
In the dodder we have no difficulty in recognizing a degenerated 
morning glory; the broom-rape is apparently a degenerated fig- 
wort, and the relationship of the mistletoe to the Santalacez is 
equally plain. The Rafflesias and the Balanophorads have suffered 
such great degradation as to almost totally obscure their affinities. 

But there are also many cases of a catagenesis not due to a de- 
pendent habit, in which we have evidence of simplification from a 
more complex structure. Thus in the willows and poplars where 
we have a raceme of very simple flowers, each consisting of a sin- 
ole ovary, or one to many stamens, it is readily seen that this sim- 
plicity is not primitive. The ovaries are not single carpels, but are 
composed of two or three united. ‘The flower of the willow is 
simple by a degeneration from a higher type, probably a tricar- 
pellary or penta-carpellary type, by the loss of its floral envelopes 
and stamens or pistils. Puzzling as the question of the relation- 
ship of the willows has been to systematists, it is no longer difficult 
to recognize in them, when viewed in the light of evolution, apeta- 
lous, declinous Tamariscineve. 

The knotworts, amaranths, chenopods, and polygonums are 


240 SECTION G. 


likewise simplified forms of well known higher types. Every bot- 
anist has recognized the close relationship of the knotworts (Il- 
lecebracez) to the pinks (Caryophyllaceze) from which they differ 
mainly in being apetalous. So close indeed is the relationship be- 
tween these two groups that in earlier editions of Gray’s Manual 
they were regarded as one, and it was only with violence that they 
were taken asunder. The amaranths (Amarantacee) evidently 
represent a similar scarious and apetalous modification of a higher 
type allied to the pinkwort Family. -In the chenopods (Chenopo- 
diaceze) there is a similar apetalous, but not scarious reduction in 
the perianth, and in other characters they are so much like the 
amaranths that they are always regarded as closely related. In 
the polygonums (Polygonaceze) the simple little flowers are so 
only by reduction from a higher type. Here the flowers have suf- 
fered little if any more reduction from the caryophylline structure 
than have the knotworts (Illecebracese), and like the latter, are 
apetalous, with a one celled, one-ovuled, pluricarpellary ovary. 
The polygonums should never have been separated from their rel- 
atives the pinks, simply because they have undergone such com- 
paratively slight modifications in structure. 

It would be easy to multiply examples like the foregoing not 
only among the Dicotyledons, but also among the Monocotyledons, 
where the rushes, aroids, palms, sedges and grasses are successive- 
ly greater reductions and simplifications of the lily type. It is, 
however, unnecessary to prolong this part of the discussion. Every 
naturalist should be as familiar with these illustrations of evolution 
by simplification as he is with those of evolution by complication. 
In the growth of the great tree of life, while the development has 
been most largely in an upward direction so that the great body of 
the tree has risen far above its point of beginning, there are yet 
multitudes of twigs and branchlets which droop downward. 

In the attempts to arrange in orderly sequence the vast assem- 
blage of living things which to-day people the earth we must con- 
stantly keep in mind the fact that they have been evolved from pre- 
existing forms. I need not now, before a body of scientific men, 
speak of evolution as an hypothesis: for we know it as a great bio- 
logical fact, as to the existence of which there is no shadow of doubt. 
A natural classification will conform strictly to the lines of evolu- 
tion, it will be in fact a clear exposition of the successive steps in 
its progress. In such a classification the primitive forms will pre- 


ADDRESS BY CHARLES E. BESSEY. . 241 


cede the derived ones, and the relation of the latter will be posi- 
tively indicated. Moreover, in such a system, there will be no 
confusion between the primitively simple forms and those which 
are so by derivation. 

An examination of our common systems shows them sadly de- 
ficient in the essentials of a scientific classification. This is partic- 
ularly true of the treatment of the flowering plants, at the hands 
of English and American botanists. We are all familiar with the 
usual sequence of the families, first the Dicotyledons, followed by 
the Monocotyledons. In the former we have in succession the 
Polypetale, Gamopetale and Apetale, the particular sequence 
being in Polypetale from those with several, separate and superior 
ovaries to those with one compound inferior ovary, while in the 
Gamopetale we begin with those with an inferior much modified 
ovary, and proceed to those with a superior less modified ovary. 
In the Apetalz we find first the plants having a superior ovary, 
than those in which it is inferior, and we finally reach a confused 
aggregation of families in which some have the ovary inferior, while 
others have it superior. When this sequence was first outlined the 
Ranunculacez and their relatives were regarded as representing 
the highest type of the Dicotyledons, and the series was therefore 
a descending one, but this was so obviously an error that without 
any material change in the sequence a new interpretation was given 
it. We now ascend from the Ranunculacee, through the Poly- 
petalz, and continue the ascent until we reach the Composite, 
after which we begin a descent to the Labiatae, thence passing into 
the Apetale we rise for a distance, and then descend again to the 
Amentacee. Nothing more unnatural could have been readily de- 
vised to represent the Dicotyledons than this undulating series, 
over whose serpentine path the young botanist wearily and confus- 
edly trudges in the company of older systematists who patiently 
endure the irregularities and inconsistencies of the familiar path. 
Nothing could show better the conservatism of botanists than the 
fact that for a third of a century after the general acceptance of 
the doctrine of evolution they are still using so crude an arrange- 
ment of the group of plants with which they are most familiar. 
Here and there a voice is raised against the continuance of this 
archaic system, and now and then one breaks his allegiance to 
Bentham and Hooker and becomes a disciple of Eichler, but the 
inconvenience, and the difficulties encountered in inaugurating the 


249 SECTION G. 


new system in the herbarium, and still more in the class room, have 
been sufficient practically to maintain the old system in our col- 
leges, universities, herbaria, botanic gardens, and what is, of more 
importance, our text-books. There are to-day but one or two 
American text-books, and these quite elementary ones, in which the 
student can learn aught of any other than the prevailing Bentham- 
ian system. In the manuals which the student uses there is no 
hint as to the relationship of the groups. The beginner soon learns 
that families which are in juxtaposition are usually more or less 
related, but he meets with some puzzling cases as when he finds 
the Labiate, Plantaginacesze and Nyctaginacev arranged side by 
side, with no word of explanation. Even in the more pretentious 
works, as in the ‘*Synoptical Flora,” and in the monographs of 
families, we have little if any discussion of the question of real 
relationship, its place being taken by a very little reference to 
what may be termed ‘descriptive affinity.” 

I may assume that it is well known to nearly all of us that the 
prevailing arrangement of the Dicotyledons does not represent the 
later views of any of the systematists. Bentham and Hooker dis 
tinctly state at the beginning of their treatment of the Apetale 
that the group is one neither natural nor well limited, and suggest 
in connection with many of the families their relationship to many 
Polypetale. While their arrangement follows the Candollean 
sequence, their explanatory notes show that the authors recognized 
the fact that the plants gathered in the group Apetalse are reduced 
forms of Polypetalee and Gamopetalee. | 

Even so conservative a writer as Dr. Gray admits! that the pre- 
vailing system consists of ‘‘tenative groupings” of the families, 
and that ‘‘most apetalous flowers are reductions or degradations 
of polypetalous types.” And yet a little later the same writer 
gives his adhesion to the Candollean system, in spite of the fact 
that he had declared? that viewed in the light of evolution ‘‘affinity 
is consanguinity, and classification in so far as it is natural, ex- 
presses real relationship.” Here we have a principle of classifica- 
tion worthy of modern science, but a practice which abandons or 
ignores it. ‘Thus he says? ‘‘the apetalous and achlamydeous must 
be the lowest,” and describes them as ‘‘those plants which, with 


Structural Botany (189), pp. 342. 344. 2? Jibd, p. 829, 8l.c. 


ADDRESS BY CHARLES E. BESSEY. 2438 


all their known relations, are most degraded or simplified by abor- 
tions and. suppressions of parts which are represented in the com- 
plete flower.” Commenting on these he says ‘‘ These are low in 
structure, equally whether we regard them as reduced forms of 
higher types, or as forms which have never attained the full de- 
velopment and diversification which distinguish nobler orders.” 
These remarks are closely followed by the presentation of a synop- 
tical view! of the ‘‘present received” system. 

The fact is, that the systematic disposition of the higher plants 
is at present a makeshift, maintained by conservatism and a rev- 
erence for the time-honored work of the fathers. It is unscientific 
to let our practice drag behind the present state of our knowledge: 
it is far more so for us to cling to the opinions of our fathers 
through mere reverence, long after we know them to be untenable. 
It is not to the credit of our science that for asecond time she has 
persistently held to a system through such considerations. For 
thirty or forty years after a natural system had been constructed 
hy Jussieu, botanists, as a body, still adhered to the artificial sys- 
tem of Linné. As late as 1830, Liudley,? in urging the abandon- 
ment of the Linnean system, refers to the current objections to 
the natural system in these words: ‘‘Its uncertainty and difficulty 
deter us, say those, who acknowledging the manifest advantages of 
the natural system, nevertheless continue to make use of the arti- 
ficial method of Linnzeus.” 

It was not until 1833 that Beck gave us the first American 
Manual,” in which the natural system was adopted. Three years 
later Dr. Gray brought out bis ‘* Elements of Botany,’ and so 
common was the Linnean system that he devotes no less than 
eighteen pages to its full exposition. He finds it necessary, 
moreover, to argue at length that the Linnean system, while 
originally adopted by its founder as a temporary substitute for a 
natural system, had ceased to be necessary or useful, and to plead 
with those who would perpetuate it to consider whether the res- 
pect due to the system be not compromised ‘‘by permitting its 
degradation to purposes for which it was not originally designed.” 

Now sixty years later we find ourselves faced with a problem 
similar to that which Lindley, Torrey, Beck, and Gray inet. His- 


1“Introduction to the Natural System of Botany,” p. xii. 
2 Botany of the Northern and Middle States,” by Lewis C. Beck. 1833. 
“Elements of Botany,” by Asa Gray, New York, 1836, 


244 SECTION G. 


tory repeats itself with such exactness, that with the change of a 
word here and there the arguments, pro and con, then used may 
be used to-day. The system of Jussieu and De Candolle is now 
as much a clog and a hinderance to the systematic botany of the 
higher plants, as was that of Linné sixty years ago; and now, as 
then, it is the spirit of conservatism and of veneration for time- 
honored usage which maintains the incubus. ! 

Manifestly a system of classification which conforms to and is 
based upon the doctrine of evolution must begin with those forms 
which are primitive, or which, as nearly as may be, represent 
primitive forms. Since the flower is a shoot, in which the phyl- 
lomes are modified for reproductive purposes, that flower in which 
the phyllomes are least modified, must be regarded as primitive, 
while that in which there is most modification must be regarded as 
departing most widely from the primitive type. The simple pistil, 
developed from a single phyllome, is primitive and lower; the 
compound pistil is derived, and higher. The several-seeded com- 
pound ovary must be lower, and the compound ovary, with but 
one seed, must be higher. Separate stamens are primitive, united 
stamens, whether the union be with one another, or with other 
structures, must be derived, and consequently higher. So, too, 
when all parts of the flower are separate, it is a primitive condi- 
tion, and when they are united it is a derived structure. 

Applying these principles to the flowering plants, it becomes 
evident that in the Dicotyledons, either the Apetale or the Poly- 
petalee must furnish our starting-point. The Gamopetale are 
universally admitted to be higher than the groups just mentioned, 
and certainly do not contain the sought-for primitive types. 
Even a hasty examination of the thirty-six apetalous families, 
shows that they are at least, to a very large extent, derived from 
the Polypetale by the abortion of some parts and the entire omis- 
sion of others. We may at once reject all of Bentham and Hooker’s 
Series I, the Curvembryez, for we have here a much modified 
compound pistil, which with other structural peculiarities, shows 
them to be reduced from the Caryophylline type. Series II 
(Podostemacez), and III (Nepenthacese, Cytinacese, and Aris- 
tolochiaceze) have compound pistils and must be rejected. In 

1]. have not deemed itnecessary to refer to the position accorded to the Gymno- 
sperms in most of our systematic works. It is so manifest an error as to need no dis- 


cussion here. The flowering plants referred to in this paper are the Angiosperms, 
both Monocotyledons and Dicotyledons, 


ADDRESS BY CHARLES E. BESSEY. | 245 


Series IV, the Piperaceze have compound pistils, and the three 
remaining families, with simple pistils, are with little doubt to be 
regarded as reduced from the Ranunculine type. Series V (the 
Daphnales) may be transferred bodily to the Celastrales in the 
Polypetale, of which they are apparently reductions. The para- 
sitic and parasitically-inclined members of Series VI (Loran- 
thacese, Santalacez, and Balanophorese) are out of the question, 
being too evidently not of primitive type. The great aggregation 
of plants, brought together under Series VII and VIII, is com- 
posed almost entirely of forms with compound, and often much 
modified, pistils. 

It appears, then, that when we search for families in the Ape- 
tale: which may satisfy the requirements of a primitive group, 
from which the Dicotyledons may have evolved, we find none which 
will serve our purpose. The dictum of Dr. Gray!, that ‘‘the 
apetalous and achlamydeous must be lowest,” is not sustained. 
We must accordingly turn to the Polypetale, where we find all 
degrees of complexity from the Ranales, with all the parts of the 
flowers simple and separate, to the Umbellales with a compound, 
inferior, much modified gyneecium. It will not be difficult to 
determine that the Ranales must take rank below all other Poly- 
petalz, in the sense of representing more nearly than any other 
group the primitive Dicotyledons. ‘This position was long ago 
suggested by the younger Jussieu,? who commenting on the fact that 
at that time most authors looking upon the flowers of the Ranuncu- 
lacese and their relatives as more perfect than any other, would place 
them at the head of the vegetable kingdom,—argued, on the con- 
trary, that the whole structure of the flower in those plants, and es- 
pecially the easy passage from the organs of vegetation to those of 
reproduction, required that they must be assigned not only to a 
lower position, but to one exactly opposite to that which they 
usually occupied. He significantly indicates that the Composite, 
with a ‘‘precisely inverse” structure, should be regarded as the 
highest of the Dicotyledons. 

The Ranales have distinct and separate perianth leaves (sepals 
and petals) ; the stamens are distinct, free from either perianth or 
pistils, and are mostly indefinite and many in number; the pistils 
are simple, free from the stamens or the perianth, and usually 


1“Structural Botany,” p. 343. 
2“The Elements of Botany.” Translated by Wilson. 1848, p. 543. 


2 


246 SECTION G. 


many; the ovules are many to few or one, and have two coats; 
the embryo is small and surrounded by a large endosperm. They 
satisfy very well the theoretical structure of a primitive dicotyle- 
donous plant, and we may well use them as the point of departure 
for our system. : 

De Candolle, and his followers in phanerogamic morphology, 
took the flower of the Ranales as their typical or pattern flower, 
and built up a morphological system in which the underlying prin- 
ciple was the theory that all the forms of flowers are due to mod; 
ifications of this archetype. We are all familiar with this treatment 
of the structure of the flower, as it is the one so clearly and ably 
set forth by Dr. Gray in his ‘‘Lessons” and ‘Structural Bot- 
any.” In accordance with this morphology the Candollean se- 
quence of the families of Dicotyledons was wrought out, the suc- 
cessive families showing greater and greater departures from the 
archetype. It is remarkable that this sequence, so established, 
did not more forcibly suggest what is now so plain that every man 
may read it—the greater principle of a genetic evolution. The old 
morphologists builded better than they knew, and though they did 
not understand it, gave us an arrangement of the principal poly- 
petalous plants which accords wonderfully with our present knowl- 
edge of the evolution of living things. Yet, they interpreted 
departure from the type or pattern flower as a lower modification, 
and at first made a descending series. 

We may, then, in the light of evolution accept in general the 
Candollean plan of arrangement of the Polypetale, as wrought out 
by Bentham and Hooker in their “Genera Plantarum,” and adapt 
it to the new view, with comparatively few changes. The apetal- 
ous families may be assigned to places near those to which they 
are evidently related, and if any remain whose relationship can- 
not be made out, they may be placed in some such convenient 
limbo as the *‘Ordines Anomali” of Bentham and Hooker, or 
the suggestive “Anhang” of the German botanists. 

Our system then begins with the Ranales, to which we have 
added.the small families Myristicacese, Monimiacedze, and Chlo- 
ranthacee. The Parietales, Polygalales, and Caryophyllales follow, 
the latter much increased by the apetalous families of the so-called 
Curvembryeze, and the Salicaceze from Bentham and Hooker’s 
‘“Ordines Anomali.” The Guttiferales and Malvales close the 
Thalamifloral series, but the latter group has been greatly increased 


ADDRESS BY CHARLES E. BESSEY. Q47 


by the addition of a number of apetalous families, viz., Piper- 
aceze, Euphorbiaceze, Balanopsez, Empetraceze, Urticacez, Leit- 
neriaceze. 

In the Disciflore, which originate near the Ranales, we have (1) 
the Geraniales ; (2) the Celastrales (in the wider sense, including 
Olacales), to which are now added the apetalous Daphnales, and 
Achlamydosporez; and (3) the Sapindales, to which have been 
added the apetalous Juglandacez, Cupuliferee, and Myricacee, 
and possibly the Casuarinee. 

Going back again to the vicinity of the Ranales, we find the initial 
point from which the Calycifloral series develops through the 
Rosales, to the Myrtales, Passiflorales, Cactales, and Umbellales, 
the highest of the polypetalous plants. 

A careful study of the Gamopetalz, while showing that they 
rank higher than Polypetalze, brings out the fact that the group is 
not a single one, and has probably arisen by development along, 
at least, two lines. From the Caryophyllales in the Thalamiflora, 
the small series Heteromersze came off, including the Ericales, 
Primulales, and Ebenales, and these connect with the Bicarpel- 
latee, composed of the Gentianales, Polemoniales, Personales, and 
Lamiales. From the summit of the Calcyflorsze we pass easily to 
the Inferze, reaching first the Rubiales, which connect equally with 
the Campanales and Asterales, the last the highest of the Dicotyle- 
dons. 

A similar examination of Bentham and Hooker’s monocotyle- 
donous groups, which they name ‘‘series,” shows that the se- 
quence which they adopt gives no idea of their probable method 
of evolution. Here their series Apocarpze (Alismales), so strik- 
ingly like the Ranales of the Dicotyledons, is without donbt the 
primitive one, and this leads easily to their Coronariez (the Liliales 
of other authors). From this central group two diverse sets of 
branches have developed, the one with a superior, and the other 
an inferior compound ovdry. In the hypogynous branches there 
is at once a reduction in the parts of the flower, as is well shown 
in the Nudifloree (Arodiales), and Calycinze (Palmales), culmina- 
ting in the Glumaceze (Glumales), which have‘so far departed 
from the lily type that at first sight it is difficult to see any rela- 
tionship. The other branch passes by easy steps through the 
Epigyne (Iridales) to the Microspermee (Orchidales). 

Such a system as is here briefly outlined, while it cannot hope to 


248 SECTION G. 


be free from grave errors, may yet claim for itself that it is an at- 
tempt at such an arrangement of the families of flowering plants 
as would be in harmony with the doctrine of evolution. 

May I beg of you that you will not underrate the importance of 
a general system, and I hardly need to remind you that unless 
the families of plants are arranged in accordance with some sys- 
tem, our classification is arbitrary and artificial. The attempt to 
make a natural system by linking family to family in a long undu- 
lating chain, by concatenation, is unscientific, because it absolutely 
fails to conform to the law of evolution. We must abandon the 
old classification and attempt one, which in the light of evolution, 
is rational. Let us not cling to the old because it is inconvenient 
to change—let us not cling to it through a mistaken reverence for 
the practice of the fathers—let us not cling to it as long as a flaw 
may be found in a new system. Science is ever abandoning the 
old, when the old is no longer the true; it tears down the work of ~ 
years, when that work no longer represents the truth ; and it dares 
to reach out and frame a rational system, even though some parts 
of it, for a time, rest upon hypothetical grounds. 


A REVISED ARRANGEMENT OF THE BENTHAMIAN ‘SERIES ” 
OF FLOWERING PLANTS. 


SUB-CLASS MONOCOTYLEDONES. 


APOCARPZ. (Alismales.) 
Alismacee, Triurides, Naiadaces. 
CORONARIEZ. (Liliales.) 

Roxburghiacee, Liliaceze, Pondeteriacee, Philydra- 
cee, Xyridaceze, Mayacez, Commelinacez, Rapa- 
teacez. | 

NuDIFLOR&. (Aroidales.) 
Pandanacee, Cyclanthacez, Typhacez, Aroidexe, Lem- 
nacee. 
CALYCINZ. (Palmales.) 
- Flagellaries, Juncacer, Palmacee. 
GLUMACEZ. (Glumales.) 

Eriocaulese, Centrolepidese, Restiacee, Cyperacee, 

Graminee. 


? 


HYDRALES. 
Hydrocharidee. 
EPIGYNZ&. (iridales.) | 
Dioscoreacew, Taccacese, Amaryllidaces, Iridacee, 
Hemodoracee, Bromeliacez, Scitaminez. 


ed 


ADDRESS BY CHARLES E. BESSEY. 249 


MICROSPERM#&. (Orchidales.) 
Burmanniacee, Orchidacee. 


SUB-CLASS DICOTYLEDONES. 


Polypetale. (Choripetale.) 
THALAMIFLOR&H. Hypogynous, apocarpous, or syncarpous. 
Ranales. 

Ranunculaceez, Dilleniaceze, Calycanthacee, Magno- 
liacez, Anonacese, Myristicacee, Monimiacee, 
Chloranthaceew, Menispermacez, Berberidacez, 
Nymphaeacee. 

Parietales. 

I. Sarraceniacezee, Papaveracee, Crucifere, Cappa- 
ridacee, Resedacex, Cistacez, Violaceze, Canel- 
lacee, Bixacez, 

II. Nepenthacee. 

Polygalales. 

Pittosporacee, Tremandracee, Polygalacez, Vochy- 

siacee. 
Caryophyllales. 

I. Frankeniacee, Caryophyllacese, Portulacacee, 
Tamariscacex, Ficoidee. 

II. Nyctaginacee, Illecebracex, Amarantacee, 
Chenopodiacee, Phytolaccacesz, Batidex, Poly- 
gonacese. 

III. Salicacee. 

Guttiferales. 

Elatinee, Hypericacee, Guttifere, Ternstromiacee, 

Dipterocarpee, Chlenacee. 
Malvales. 

I. Malvacee, Sterculiaces, Tiliacex. 

Il. Euphorbiacee, Balanopsex, Empetracee. 

Ill. Urticaces, Platanacese, Leitneriacex, Cerato- 
phyllacee. 

IV. Piperaces (?), Podostemacez. 

DIscirFLORZ. Hypogynous, syncarpous. 
Geraniales. 

Linacee, Humiriacee, Malpighiacee, Zygophyl- 
laces, Geraniacee, Rutacex, Simarubacex, Och- 
nacee, Burseracee, Meliacee, Chailletiacez. 

Celastrales. 

I. Olacacee, Ilicinee, Celastracexr, Stackhousiex, 
Rhamnacez, Ampelidee. 

II. Uauraces, Proteacee, Thymeleacee, Pene- 
aces, Kleagnacee. 

III. Santalacez, Loranthacez, Balanophoracez. 

Sapindales. 
I. Sapindacez, Sabiacez, Anacardiacee. 
Il. Juglandacee, Myricacex, Cupulifere. 


250 ) SECTION G. 


III. ? Casuarinaceex. 
CALYIFLORA. Epigynous, syncarpous. 
Rosales. 

Connaracesz, Leguminose, Rosaceex, Saxifragacee, 
Crassulaceze, Droseracee, Hamamelidacez, Bruni- 
acee, Haloragez. 

Myrtales. 

I. Rhizophorese, Combretacesw, Myrtacez, Melas- 

tomaceez, Lythracez, Onagracee. 
II. ?Aristolochiacezs, Cytinacee. 
Passiflorales. 
Samydacezr, Loasaceze, Turneracee, Passifloracee, 
Cucurbitaceze, Begoniacezx, Datiscaceze. 
Cactales. 
Cactacez. 
Umbellales. 
Umbellifere, Araliacee, Cornacee. : 


Gamopetale. 


HETEROMER. Ovary, mostly superior. 
Primulales. 
Plumbaginaceex, Plantaginacez, Primulacez, Myrsi- 
nace. 
Ericales. 
Vacciniaceew, Ericacee, Monotropee, Epacridee, 
Diapensiacez, Lennoacee. 
Ebenales. 
Sapotaces, Ebenacee, Styracacee. 
BICARPELLAT&. Ovary mostly superior; stamens and petals isomerous; 
ovary, bi-carpellary. 
Gentianales. 
Oleacez, Salvadoracez, Apocynacee, Asclepiadacee, 
Loganiacese, Gentianacee. 
Polemoniales. 
Polemoniacez, Hydrophyllacee, Boraginacez, Con- 
~ volvulacee, Solanucee. 
Personales. 
Scrophulariacee. Orobanchacee, Lentibulariacer, 
Columelliaces, Gesneracez, Bignoniacez, Pedali- 
acez, Acanthaceee. 
Lamiales. 
Myoporinee, Selaginesze, Verbenacex, Labiate. 
INFER&. Ovary inferior, stamens and petals isomerous. 
Rubiales. 
Caprifoliaceze, Rubiacee. 
Campanales. 
* Stylidacez, Goodenoviee, Campanulacee. 
Asterales. 
Valerianacez, Dipsacez, Calyceraceex, Composite. 


*, 


251 


ADDRESS BY CHARLES E. BESSEY. 


ASTERALES.. LAMILES. 
: & 
A 
az PERSONALES. FZ 
e z - 
tS <L 2 Ly 
TZ Ye OL EMONALES. 
= t) CaPANALES. a 
a4 ea GENTIANALES. B 
= z= EBENALES. 
2s uj , 
cioNe 
BIALES. SAPINDALES. 
a fib PRIM UL. ALES. Se? Cun: 
<=} = CHG E ree re 
= UMBELLALES. Q= oe <s Ss Santal. 
ay €v Flaeagnaceae. 
= - leer re A oO Louracéae. 
Ww — CACTALES. CQRANIALES. 
is 
O ss IMALVALES — fuphorhiaceae. 
NM YRTA)LES. ee caceae 
TE C Dy, Piperaceae. 
ae RY. LLALES. ia 
2 FARIETALES. One ey, Fi sh Rte 
7a? ewe 
[ < SS Chenopodiaceae. 
Salicacece 


FANN 


3 0112 2 09901 5825 


